Safety standards and measurement techniques for high intensity light sources

Any analysis of the retinal hazards of ophthalmic instrumentation based on criteria derived from current standards which implicitly assume large eye movements and smaller pupil sizes than are present in many diagnostic and therapeutic situations requires some care in application. Simple measurements of the optical power from a source with the calculation of the total retinal irradiance are not sufficient for hazard evaluation. Thorough and reliable hazard analysis requires knowledge not only of the spectral irradiance and the imaging conditions, but also some quantitative assessment of any pathological changes possibly producing unusual susceptibility in the patient's eyes.